Its always better to provide more file types and support the different software apps but not everyone uses or has a Substance painter license.
For example I paint in 3D coat in combination with Photoshop, 3D coat can output the layers to PSD format so you can have a direct link with photoshop. I usually provide this PSD file so someone ells can import same project in 3D Coat or maybe Substance painter.
If I would use Substance painter and substance materials then I would provide those file types along with PSD and regular textures.
PS: Substance painter has no support for 3D space mouse, that's the main reason I don't use it, navigating a 3D scene with buttons is plane ridicules, I use a 3D mouse for about 8 years now and stopped using apps that have no support for it and I’m not the only one doing this.